Joseph Plumeri, CEO of insurance giant Willis Holdings Group, filed a lawsuit alleging $3 million worth of defects were undisclosed before he purchased his 995 Fifth Avenue co-op for $20.5 million in March 2010, the New York Post reported. He is seeking $12 million in damages from Extell Development, which converted the former Stanhope Hotel into the co-op.

Plumeri said he began renovating his five-bedroom, 7.5-bathroom unit just months after buying it because it came with defective waterproofing, poor installation of floors and soundproofing, bad fireproofing, and structural problems. Once Plumeri completed what he deems costly upgrades, the apartment was allegedly damaged by a water leak from the upstairs unit, which the suit claims was similarly defective.

Plumeri wants Extell to pay for his repairs and to fix the apartment upstairs. But a spokesperson for the development firm said the suit “has no merit.” [Post]